Nailing down complicated international trade agreements, with a zillion different interests and moving parts, is no easy feat. The Obama administration is trying to do two at once, one with the European Union and another with nine countries in Asia, both of which will be monumental feats when they're finally signed.

But that's not the half of it: Obama's emissaries also have to wrangle with Congress.

In order for the agreements to be signed, the administration says it needs the power to put them to a vote without legislators being able to make amendments as they would with normal legislation--a "fast track" to approval. And guess who has to grant the president that power? That's right--Congress itself. This year, it's shaping up to be just as big a fight over checks and balances as the filibuster brinksmanship, only with different battle lines, and the rest of the world watching closely.

Trade policy's expanding scope

The Constitution gives Congress the authority to approve treaties with other countries. For much of the century, this wasn't a problem: Trade policy was just about tariffs, and Congress simply set them.

In the 1970s, however, President Richard Nixon wanted to negotiate around more complex issues, like government procurement and intellectual property laws. It was hard to do that when America's trading partners knew the whole agreement could unravel in Congress, so Nixon asked for--and got--a law that allowed him to put the signed treaty to a vote without amendments. It was a strange historical moment: One branch of government voluntarily relinquishing some of its power to make sure America could negotiate effectively overseas.

"It's hard to see if Congress could ever pass a deal if any kind if it amended every line of every proposed trade agreement," says James Bacchus, a former member of Congress who served as a judge at the World Trade Organization and now chairs Greenberg Traurig's global trade practice. "This is not just a negotiation among ourselves. This is a negotiation of other countries, and we need to understand what were trying to accomplish."

A periodic fight

But Trade Promotion Authority, as it's now called, doesn't last forever--it has to be re-gifted every five years. And not every president has been as successful as Nixon. It's usually a fight, requiring the president to cut deals with congressional gatekeepers in advance of the deal taking shape.

"Back in 1991, right after I was elected to Congress, I called [U.S. Trade Representative Carla Hills] as a congressional Democrat to assist in getting President Bush trade negotiating authority," Bacchus remembers. "Carla almost fell out of her chair."

Having fast track authority makes big, controversial deals much more feasible: With it, President Bill Clinton was able to finish the North American Free Trade Agreement that Bush had started. But it's not essential for passing more pedestrian trade agreements. Though Clinton failed to get fast track reauthorized after it expired again in 1994, he was still able to get trade deals done, though Congress sometimes took its time in signing them.

And granting a president fast track authority also doesn't mean Congress relinquishes all power: President George W. Bush's version of fast track--authorized in 2002, by a 215-212 House vote--built in a whole bunch of "objectives" that the negotiations were supposed to abide by.

The last iteration of fast track expired in 2007. And yet, two of the biggest trade deals ever are well underway. Isn't that supposed to be influencing the negotiations?

"I suspect it is not," says Thomas Bollyky, a former negotiator for the U.S. Trade Representative who's now at the Council on Foreign Relations. "And it is not because both sides have assumed it will be there. Everybody is pretending it still exists."

The Baptist-Bootlegger Coalition

That's a lot of faith. Congress is already expressing reservations: A collection of Democratic House freshmen sent a letter opposing fast track authority on the grounds that today's trade agreements involve changing vast swaths of domestic policy, and they'd like to maintain a hold on the process, especially since the Trans-Pacific Partnership negotiations have been kept so secret. Sen. Sherrod Brown wants to see all sorts of requirements built in, like language around Chinese currency manipulation.

Then there are the tea party Republicans and isolationists who worry about the political consequences of yielding so much power to a president they don't trust--especially when fast track would allow him to slip unrelated provisions into enabling legislation that would have to be voted up or down.

"There are a lot of members who're saying, 'you've treated me abysmally, why would I give myself handcuffs involuntarily?'" says Lori Wallach of Public Citizen, which opposes fast track. "It means the president can dictate domestic policy on a whole range of issues. And they can implement all sorts of unpopular provisions, and superglue them into a trade agreement."

Stanford professor Judith Goldstein calls this emerging dynamic a "Baptist-bootlegger coalition," referring to the Prohibition-era partnership of temperance crusaders and the moonshine makers who wanted to keep prices high. It's a loose analogy, but in this case, historically labor-aligned groups are the bootlegger, and the Ron Paul-style conservatives are the Baptists.

"If consumer groups think that they have a better deal picking up individual congressmen, they're not going to want any deal that makes it harder for them to get access," she says. "My guess is it's just another way of saying they don't want a trade deal."

And Goldstein doesn't give fast track good odds of passing this year. "I would be pleased, but shocked."

Business, Obama, and…GOP Leadership?

On the other side, however, lies all the force of American industry: An array of business lobby groups, from the Farm Bureau to the National Association of Manufacturers, have been pushing for trade promotion authority all year. The Chamber of Commerce says it's the organization's top legislative priority; its officials have even started running ads on the issue, have already met with all the House freshmen, and are planning meetings with the sophomores.

"It's really urgent to get this done, because the U.S. is engaged in a lot of negotiations right now," says Chris Wenk, the Chamber's point person on trade issues. "I think it's safe to say that if there's not some clarity about trade promotion authority, some of our trade partners might not put their best feet forward."

Unlike the filibuster fight, this is a rare instance where top Republicans are actually willing to grant the Obama administration more authority, because modern trade deals typically involve less regulation, rather than more. And granting fast track authority is usually understood as a signal to trade partners that the U.S. is serious.

But if it doesn't get done, and Congress finds that it really objects to the final agreement, it could always change the rules again.

"if you talk to legislators, they talk about it like it's a rule, like it's something that actually constrains them," says Goldstein. "It serves as a credible commitment, but one that can be broken…so much of politics is symbolic."

Lydia DePillis is a reporter focusing on labor, business, and housing. She previously worked at The New Republic and the Washington City Paper. She's from Seattle.

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